Session 1 SCRIPTING LANGUAGES 08-10-2018 WEN-CHI YANG Your first - PowerPoint PPT Presentation

Session 1 SCRIPTING LANGUAGES 08-10-2018 WEN-CHI YANG

Your first program

Find the file 2. Click here 3. Copy the path 1. Find the file

Find the file 4. Go to the folder where your file locates by using cd Check if your file is here by using ls

Find the file 5. type python <filename> to execute your program

REPL READ-EVALUATE-PRINT-LOOP

Read-Evaluate-Print-Loop ➢ An interactive program ➢ Useful for testing short snippets of Python code ➢ Type quit() to stop REPL

Classroom Exercises

Comments ➢ Everything behind # is ignored ➢ Exercise 1

Data types ➢ Booleans : True , False ➢ Integers : …, -2, -1, 0, 1 , 2, 3, … ➢ Floating-point numbers : 1.0, 0.33, -3.14159 , …. ➢ Strings : “Hello world!” ➢ Exercise 2

Boolean Operators ➢ not True is False , not False is True ➢ P and Q is True only when both P and Q are True ➢ P or Q is True when either P or Q is True P Q not P P and Q P or Q F F T F F F T T F T ➢ Exercise 3 T F F F T T T F T T

String Formatting ➢ %s for strings ➢ %d for integers ➢ %f for floating numbers ➢ \n inserts a line break, \t inserts a tab ➢ Exercise 4.1 & 4.2

Datetime ➢ today = datetime.date.today() # an object ➢ today.day # an attribute ➢ today.month ➢ today.year ➢ Similar for datetime.datetime.now() ➢ exercise 5.1 & 5.2

String concatenation ➢ Use + to concatenate strings, e.g. “hello” + “ world!” ➢ Try to print a digit with %d, %2d and %02d ➢ Observe ➢ Exercise 6

Challenge exercise: painting